Proteinaceous, lipid and other non-proteinaceous deposits build up on contact surfaces while being worn. The deposits, derived from mucus, oils, cosmetics, protein from tear fluid, and the like, not only can result in discomfort to the contact lens user, but an also impair vision and reduce wearing time unless such deposits are removed.
Traditional cleaning solutions generally help to remove many, but not all, such deposits. Particularly difficult to remove are proteinaceous deposits. Accordingly, various heterogeneous suspensions for use in removing such deposits have been proposed. Typically, such compositions contain a water-insoluble particulate material, such as a silica abrasive or polymer microbeads, in a suitable liquid carrier vehicle, such as water thickened with a viscosity modifier. See, for example, U.S. Pat. Nos. 4,493,783 and 4,394,179.
While such compositions are generally useful in removing such deposits, the presence of residual water-insoluble particulate materials on the contact lens surface can result in patient irritation or even corneal abrasions. Therefore, in using such prior art heterogeneous suspensions, thorough rinsing of such lenses is indicated.
It would be highly desirable to obviate the need for thorough rinsing to remove particulate material arising from the cleaner composition.
It has now been surprisingly found that drawbacks associated with the use of such heterogeneous compositions of the prior art can be obviated, while still retaining the cleansing advantages associated with heterogeneous suspensions, by employing a water soluble particulate compound suspended in a predominately non-aqueous water-miscible organic liquid medium, as described hereinafter.
Thus, it is an object of the present invention to provide the artisan with a method of cleaning hard and soft contact lenses by applying such compositions to the lens surfaces, and rubbing the lens surface in the presence of such compositions to remove proteinaceous and non-proteinaceous deposits, and subsequently contacting the cleaned lenses with an aqueous medium to dissolve and remove any associated particulate lens cleaning material from the lens surfaces.
It is a further object of the present invention to provide the artisan with compositions useful in such method.
These and other objects of the present invention are apparent from the following disclosures.